@Henrik ****
2 months at a time is OK with me if/when Thailand sorts itself out for a 2-month visa-free on arrival and one Bt1900 30-day extension, which will be convenient for 99% of Thai Tourists. 3 months for Bt1900 for a 90-day holiday is OK by me and many others. It's only the long-term residents that now have something to worry about and may have to pay income tax in Thailand...maybe???
It is unlikely that Australians who get the Australian Aged Pension (AAP) and some super are likely to be free of Thai income tax. The AAP in Australia is not taxed if you are under the ATO threshold and super now has already been deducted of 15% of the profits. Any dividends are then or now tax-free in Australia and most likely in Thailand.